Bob: I use the tubes sold by Phil Davis and I have had very good results with my 4x5 film. The overall evenness is better than I was able to achieve with tray developing. However, some of the process does take place in trays. Once you get to the fixer, the sheets come out of the tubes and it's done in a tray of fixer. Let me know if you want more info. Good luck.(posted 9070 days ago)